Method and system for improving security of postage indicia utilizing resolution and pixel size

ABSTRACT

The present invention includes methods for printing and verifying postage indicia. At least a portion of the indicia is printed with a resolution characteristic that may be changed from indicium to indicium. Each indicium includes data that indicates the resolution used to print the indicium or indicium portion.

BACKGROUND

This invention relates generally to the field of postal revenueprotection, and more particularly to generating postage indicia in amanner that enhances opportunities to detect counterfeiting of postageindicia.

Postage meters are well known. An important aspect of any system thatincludes postage meters is protection of postal revenue and preventionand deterrence of postage indicia counterfeiting. While currentlyavailable systems generally operate satisfactorily in this regard, itwould be desirable to provide a postage metering system which includesincreased opportunities for detecting counterfeiting of postage indicia.

SUMMARY

Accordingly, apparatus and methods for generating and inspecting postageindicia are provided.

In one aspect, an apparatus includes a print element for printing anindicium on a substrate, where at least a portion of the indicium isprinted with a first resolution. The apparatus further includes acontrol mechanism that is coupled to the print element to cause theprint element to print at least one symbol as part of the indicium,where the at least one symbol includes resolution data that isindicative of the first resolution. (As used herein, “resolution” refersto a fineness of detail in a printed image.) The first resolution mayinclude a horizontal resolution factor and a vertical resolution factorthat is different from the horizontal resolution factor.

The control mechanism may cause the print element to print theresolution data in encrypted form. The at least one symbol that includesthe resolution data may be at least part of a barcode such as atwo-dimensional barcode.

The control mechanism may operate to select the first resolution invarious ways, including a random or pseudo-random process. As usedhereinafter, a “random process” refers to any process in which a degreeof randomness or pseudo-randomness enters into selection of a resolutioncharacteristic.

According to another aspect, a method includes examining an indicium todetermine a first print resolution characteristic of at least a portionof the indicium, and reading at least one symbol included in theindicium to determine a second print resolution characteristic indicatedby resolution data represented by the at least one symbol. The methodfurther includes comparing the first print resolution characteristicwith the second print resolution characteristic to determine whether thefirst print resolution characteristic matches the second printresolution characteristic.

The reading step may include reading a barcode that is part of theindicium. The barcode may be a two-dimensional barcode. The indicia maybe postage indicia.

According to still another aspect, a method of printing a postageindicium by using a postage meter includes selecting a print resolutionbased on at least one of: (a) a calendar date, (b) a current day of theweek, (c) a state or province in which the postage meter is located, (e)a current value of a register of the postage meter, and (f) a randomprocess. The method further includes printing at least a portion of thepostage indicium with the selected print resolution.

By printing postage indicia, or a portion thereof, with a resolutionthat may be changed from indicium to indicium (or, e.g., from batch tobatch of mail pieces) and encoding in each indicium data that indicatesthe resolution employed for printing the indicium or portion of theindicium, the invention may make it more difficult to counterfeitpostage indicia and may aid in inspection and verification of postageindicia.

Therefore, it should now be apparent that the invention substantiallyachieves all the above aspects and advantages. Additional aspects andadvantages of the invention will be set forth in the description thatfollows, and in part will be obvious from the description, or may belearned by practice of the invention. Various features and embodimentsare further described in the following figures, description and claims.

DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate presently preferred embodiments ofthe invention, and together with the general description given above andthe detailed description given below, serve to explain the principles ofthe invention. As shown throughout the drawings, like reference numeralsdesignate like or corresponding parts.

FIG. 1 is a block diagram that illustrates an indicia printing apparatusarranged in accordance with principles of the present invention.

FIG. 2 is a flow chart that illustrates a process that may be performedby a processing/control component that is part of the apparatus of FIG.1.

FIG. 3 is an illustration of a specimen postage indicium of a type thatmay be printed by the apparatus of FIG. 1.

FIG. 4 is a schematic illustration that shows a simple example of bothan image of a portion of an indicium that may be printed by theapparatus of FIG. 1 and a source image bit map for the printed image.

FIG. 5 is a schematic illustration that shows a simple example ofanother source bit map suitable for producing an image having adifferent resolution from the image of FIG. 4.

FIG. 6 is a schematic illustration that shows an image produced on thebasis of the bit map of FIG. 5.

FIG. 7 is a schematic illustration that shows a simple example of stillanother source bit map suitable for producing an image having adifferent resolution from the images of FIGS. 4 and 6.

FIG. 8 is a schematic illustration that shows an image produced on thebasis of the bit map of FIG. 7.

FIG. 9 is a schematic illustration that shows a simple example of yetanother source bit map suitable for producing an image having adifferent resolution from the images of FIGS. 4, 6 and 8.

FIG. 10 is a schematic illustration that shows an image produced on thebasis of the bit map of FIG. 9.

FIG. 11 is a flow chart that illustrates a process that may be performedto verify postage indicia printed by the apparatus of FIG. 1.

DETAILED DESCRIPTION

The present invention includes apparatus and methods for printing andverifying postage indicia. The indicia or a portion of the indicia maybe printed in accordance with a particular resolution characteristicthat may be changed from indicium to indicium, from one batch of mailpieces to another, or from one period of operating the postage indiciaprinting apparatus to another. Data is encoded into each indicium thatindicates the resolution characteristic used to print the indicium orportion of the indicium. To verify the indicium, the indicium isexamined, for example, by an optical magnification system, to detect theparticular resolution characteristic, and the data encoded in theindicium concerning the resolution characteristic is read. The detectedresolution characteristic is compared with the data to determine whetherthere is a match. If so, the authenticity of the indicium may beconsidered to be verified.

Referring now to the drawings, and particularly to FIG. 1, the referencenumeral 20 indicates generally an apparatus for printing postage indiciain accordance with principles of the present invention. The printingapparatus 20 includes a print element 22 that is configured to printindicia (not shown in FIG. 1) on mail pieces (e.g., an envelopes),labels or another type of substrate, indicated by reference numeral 24.In some embodiments, the print element 22 may be an ink jet or laserprinter that is capable of printing text, images, and/or barcodes with amatrix of dots or pixels. In some embodiments, the print element 22 maybe of a type conventionally employed as part of a postage meter system.

The printing apparatus 20 also includes a processing and control block26, which is coupled to and controls the print element 22. The couplingof the processing and control block 26 to the print element 22 may bevia a data channel 28. In accordance with conventional practices, thedata channel 28 may be secured by encryption and/or decryption performedin the processing and control block 26 and/or the print element 22. Theprint element 22 may be implemented with two or more print elements. Insome embodiments, hardware aspects of the processing and control block26 may be constituted by conventional electronics used to control knowntypes of postage meters, but programmed with software provided inaccordance with principles of the present invention. (Program storageand working memory aspects of the processing and control block 26 arenot separately shown.) In general, all hardware aspects of the postageindicia printing apparatus 20 may, in some embodiments, be constitutedby a conventional postage metering system, but as noted above theprocessing/control block 26 may be programmed and operated in accordancewith principles of the present invention. The postage indicia printingapparatus may be suitable for installation and operation with aconventional mailing machine, which is not shown.

FIG. 2 is a flow chart that illustrates a process that may be performedby the processing and control block 26 of the printing apparatus 20. Theprocess of FIG. 2 begins with a step 40 in which the processing andcontrol block 26 selects a resolution characteristic to be employed inprinting some or all of an indicium. The resolution characteristic maybe represented, for example, by a horizontal resolution factor and avertical resolution factor. For example, the print element 22 may becapable of printing with a certain maximum resolution (maximum dots perinch or dpi) in the horizontal and vertical directions. The maximumvertical resolution is limited by the size of the print head, while themaximum horizontal resolution is based upon the system design. Thehorizontal resolution factor may indicate a degree to which the actualhorizontal resolution to be employed in printing the indicia or portionthereof is to be increased, whereas the vertical resolution factor mayindicate a degree to which the actual vertical resolution to be employedin printing the indicia or indicia portion is to be increased.

The expression “HxVy” may be taken as an indication of a resolutioncharacteristic of a printed image based on a source image bit mapselected by the processing and control block 26, where “Hx” represents ahorizontal resolution factor, i.e., transformation of each pixel in ahorizontal direction, and “Vy” represents a vertical resolution factor,i.e., transformation of each pixel in a vertical direction. Thus, theexpression “H1V1” indicates a resolution characteristic in which eachpixel of the printed image corresponds to a pixel of the source imagebit map. The expression “H2V1” indicates a resolution characteristic ofthe printed image in which the pixels in the horizontal direction areincreased by a factor of two, while there is no change to the pixels ofthe source image in the vertical direction. The expression “H1V2”indicates a resolution characteristic of the printed image in which thepixels of the source image are increased in the vertical direction by afactor of two, while there is no change to the pixels in the horizontaldirection. The expression “H2V2” indicates a resolution characteristicof the printed image in which each pixel is increased in both thehorizontal and vertical direction by a factor of two.

In some embodiments, the postage indicia printing apparatus 20 may beprogrammed to select only from among the four resolution characteristicsH1V1, H2V1, H1V2 and H2V2. In other embodiments, the horizontal and/orvertical resolutions may be varied by factors other than two, and thenumber of potential choices of resolution characteristics may be greaterthan four. In still other embodiments, the number of potential choicesof resolution characteristics may be less than four. In addition, insome embodiments the number of potential choices of resolutioncharacteristics may be four although the possible degree of increase ofhorizontal and/or vertical resolution may be other than by a factor oftwo.

In some embodiments, the resolution characteristic selection may bebased on one or more of: the current date, the day of the week, thecurrent month, the state or zip code of origin of the mail, a currentpostage meter register value (e.g., the last digit of the current valueof the ascending meter register). In addition or alternatively, theselection of the resolution characteristic may be based at least in parton a command or data downloaded to the postage indicia printingapparatus 20 from a central data center upon recharging the postageindicia printing apparatus with postage.

In some other embodiments, the resolution characteristic may be based ona random or pseudo-random process. For example, the processing andcontrol block 26 may include a random number generator (not separatelyshown), and on the basis of a random number generated by the randomnumber generator, a look-up table (not separately shown) may be accessedto select a resolution characteristic indicated by an entry in thelook-up table.

Following (or, alternatively, prior to) step 40 is a step 42 at whichpostage meter data, such as, for example, the ascending register valueand postage amount, is received. As is well known to those who areskilled in the art, an ascending register value is a value that isconventionally stored in a postage meter to indicate the total amount ofpostage that has been dispensed by the postage meter. The ascendingregister value may be received, for example, by reading a register thatmay be maintained in a non-volatile memory (which is not separatelyshown). The postage amount may be set in a conventional manner, e.g., bymanual input or by data received from a postage scale (not shown) whichis interfaced to the printing apparatus 20. The receiving of the postageamount data may include, for example, either receiving manual input froma human operator or receiving postage amount data output from a postagescale.

Following steps 40 and 42 is a step 44 at which encrypted data isproduced by an encryption process that includes the selected resolutioncharacteristic, as well as other postage meter data, as inputs and issuch that the resolution characteristic and the postage meter data canbe recovered by decrypting the encrypted data.

Step 46 follows step 44. At step 46 the printing apparatus prints apostage indicium. In particular, the processing and control block 26controls the print element 22 to print the indicium on the substrate 24.As will be seen, the encrypted resolution characteristic is included inthe indicium in the form of one or more machine-readable symbols.

FIG. 3 is an illustration of a specimen postage indicium 60 of a typethat may be printed by the printing apparatus 20 (FIG. 1) at step 48(FIG. 2). Referring to FIG. 3, the indicium 60 may include conventionalelements such as a postage amount 62 (in human-readable numerals), apostmark 64 (including date and location of mailing) and amanufacturer's icon, logo or trademark 66. The indicium 60 may furtherinclude a meter serial number 68 in the form of human-readable numerals.The indicium 60 also includes a barcode 70 by which machine-readabledata is presented. The data represented by the barcode 70 includes theencrypted resolution characteristic data that was referred to above inconnection with step 44 (FIG. 2). Other data may be included in thebarcode 70, such as machine-readable versions of the meter serial numberand the postmark information and/or destination information such as thedestination zip code. The indicium may generally be in compliance withthe “Information-Based Indicia Program” (IBIP) promulgated by the U.S.Postal Service. The IBIP information may contain high-density variablecryptographically protected information in a two-dimensional barcode.The IBIP information may be used for security and marketing purposes andmay include the encrypted resolution characteristic data referred toabove. In compliance with the IBIP, the barcode may be based on the wellknown PDF417 standard or Data Matrix standard.

It will be appreciated that the barcode 70 constitutes machine readablesymbols that include resolution characteristic data which indicate theresolution characteristic selected by the postage indicia printingapparatus 20 at step 40 in FIG. 2. In other embodiments, the resolutioncharacteristic data may be presented by other types of symbols, whichmay or may not be machine-readable. For example, one-dimensionalbarcodes and/or alphanumeric characters may be employed to represent theresolution characteristic data as part of the indicium 60. It is notrequired that the resolution characteristic data be encrypted.

If the resolution characteristic data is printed in encrypted form, theencryption process need not include either or both of ascending registerdata and postage amount data as inputs, and/or may include some or allof other data such as calendar date data, meter serial number data,address data, and so forth.

There will now be described, with reference to FIGS. 4-10, simplifiedexamples of images that may be printed as part of the indicium 60 inaccordance with various resolution characteristics.

FIG. 4 shows an example of an image printed with an H1V1 resolutioncharacteristic. For the purposes of FIG. 4 and the other images shown inFIGS. 6, 8 and 10, it is assumed that the images occupy a field that is32 pixels across and 16 pixels high. In practice, the indicium orindicium portion that is printed in accordance with varying resolutioncharacteristics may be larger or smaller than a field of this kind.Also, contrary to the examples shown in FIGS. 4, 6, 8 and 10, inpractice the pixels may be so small as not to be visible except with theuse of an optical magnification system.

In some embodiments, the image shown in FIG. 4 may be generated on thebasis of a bit map which is also 32×16 pixels and which may be identicalto the resulting image shown in FIG. 4.

FIG. 5 shows an example of a source image bit map that may be used togenerate a printed image in accordance with an H2V2 resolutioncharacteristic. The source image bit map of FIG. 5 is 16×8 pixels. FIG.6 shows an example 32×16 image generated from the source image bit mapof FIG. 5 with an H2V2 resolution characteristic. The image of FIG. 6 isgenerated from the source image bit map of FIG. 5 by transforming eachpixel of the source image bit map of FIG. 5 into a 2×2 array ofcorresponding pixels. For example, pixels S1 and S2 of the source imagebit map of FIG. 5 are transformed to pixel groups P1 and P2,respectively, of the printed image of FIG. 6. The remaining pixels,S3-S16 of the source image bit map are likewise transformed to acorresponding pixel group P3-P16 in the printed image. Thus, each sourcepixel is transformed into four printed pixels, two in the horizontaldirection and two in the vertical direction (H2V2).

FIG. 7 shows an example of a source image bit map that can be used toprint an image with an H1V2 resolution characteristic. The source imagebit map of FIG. 7 is 32×8 pixels. FIG. 8 shows an example 32×16 imagegenerated from the source image bit map of FIG. 7 with an H1V2resolution characteristic. The image of FIG. 8 is generated from thesource image bit map of FIG. 7 by transforming each pixel of the sourceimage bit map of FIG. 7 into a 1×2 array of corresponding pixels. Forexample, pixels S1 and S2 of the source image bit map of FIG. 7 aretransformed to pixel groups P1 and P2, respectively, of the printedimage of FIG. 8. The remaining pixels of the source image bit map arelikewise transformed to a corresponding pixel group in the printedimage. Thus, each source pixel is transformed into two printed pixels inonly the vertical direction (H1V2).

FIG. 9 shows an example of a source image bit map that can be used toprint an image with an H2V1 resolution characteristic. The source imagebit map of FIG. 9 is 16×16 pixels. FIG. 10 shows an example 32×16 imagegenerated from the source image bit map of FIG. 9 with an H2V1resolution characteristic. The image of FIG. 10 is generated from thesource image bit map of FIG. 9 by transforming each pixel of the bit mapof FIG. 9 into a 2×1 array of corresponding pixels. For example, pixelsS1 and S2 of the source image bit map of FIG. 9 are transformed to pixelgroups P1 and P2, respectively, of the printed image of FIG. 10. Theremaining pixels of the source image bit map are likewise transformed toa corresponding pixel group in the printed image. Thus, each sourcepixel is transformed into two printed pixels in only the horizontaldirection (H2V1).

The images of FIGS. 4, 6, 8 and 10, taken together, schematicallyillustrate how, at least under optical magnification, it is possible todetermine by examination of an indicium or indicium portion whatresolution characteristic was employed to print the indicium or indiciumportion. In some embodiments, variations in the resolutioncharacteristic may not be detectable with the naked eye.

In some embodiments, it may be preferable not to vary the resolutionemployed to print the barcode 70, in the event that varying theresolution employed to print the barcode 70 may interfere with machinereading of the data contained in the barcode. In some embodiments, someor all of a graphical image portion of the indicium (e.g., the icon 66,FIG. 3) may be the portion of the indicium for which varying resolutionmay be employed. In addition or alternatively, some or all of thealphanumeric characters of the indicium may be subject to printing witha varying resolution.

An operation to verify an indicium printed by the postage indiciaprinting apparatus 20 will now be described with reference to the flowchart shown in FIG. 11. The process of FIG. 11 begins with a step 80 atwhich a barcode reader (not shown) reads the barcode 70 of the indicium.Next, at step 82, the resolution characteristic data included in thebarcode is decrypted (by, e.g., a computer (not shown) to which thebarcode reader is coupled). Before, during or after steps 80 and 82, theindicium or a certain portion thereof is examined (by, e.g., using anoptical magnification system) to determine the resolution characteristicin accordance with which the indicium or indicium portion was printed.This step is indicated at 84 in FIG. 11.

Next, at step 86, the resolution characteristic detected at step 84 iscompared with the resolution characteristic read from the barcode anddecrypted by the barcode reader/computer at steps 80, 82. For example,the barcode reader/computer may provide output to indicate theresolution characteristic represented by data in the barcode.

A decision block 88 may follow or form part of step 86. At decisionblock 88, it is determined whether the two resolution characteristicsmatch. If so, the indicium can be considered verified (step 90). If thetwo resolution characteristics are determined not to match, the indiciummay be found to be counterfeit (step 92).

In some embodiments, one or both of the resolution characteristics maybe checked with data stored in an indicia verification data center toconfirm that the resolution characteristic complies with instructions orrequirements to determine the appropriate resolution characteristic forthe indicium under examination.

With a system as described herein, including printing of resolutioncharacteristic data in a postage indicium, and examination of theindicium to determine whether the indicium or a portion thereof has beenprinted in accordance with a resolution characteristic that matches theresolution characteristic data, verification of postage indicia can befacilitated, and counterfeiting of postage indicia can be more easilydetected and deterred.

In addition to verifying indicia based on resolution characteristicsdetermined by examination and stored as data in the indicia, otherprocedures may also be employed to verify the authenticity of theindicia.

In some embodiments, there may be two or more portions of the indiciumfor which the resolution characteristic may be changed from indicium toindicium, and the barcode may include resolution characteristic datacorresponding to each of those indicium portions.

The words “comprise,” “comprises,” “comprising,” “include,” “including,”and “includes” when used in this specification and in the followingclaims are intended to specify the presence of stated features,elements, integers, components, or steps, but they do not preclude thepresence or addition of one or more other features, elements, integers,components, steps, or groups thereof.

A number of embodiments of the present invention have been described.Nevertheless, it will be understood that various modifications may bemade without departing from the spirit and scope of the invention. Thepresent invention may be applied, for example, to verification ofindicia other than postage indicia. Other variations relating toimplementation of the functions described herein can also beimplemented. Accordingly, other embodiments are within the scope of thefollowing claims.

1. An apparatus comprising: a print element for printing an indicium ona substrate, at least a portion of the indicium being printed with afirst resolution; and control means coupled to the print element forcausing the print element to print at least one symbol as part of theindicium, the at least one symbol including resolution data that isindicative of the first resolution.
 2. The apparatus according to claim1, wherein the first resolution includes a horizontal resolution factorand a vertical resolution factor.
 3. The apparatus according to claim 2,wherein the vertical resolution factor is different than the horizontalresolution factor.
 4. The apparatus according to claim 1, wherein thecontrol means causes the print element to print the resolution data inencrypted form.
 5. The apparatus according to claim 1, wherein the atleast one symbol is part of a barcode.
 6. The apparatus according toclaim 1, wherein the control means is operative to select the firstresolution.
 7. The apparatus according to claim 6, wherein the controlmeans is operative to select the first resolution based at least in parton a random process.
 8. A method for printing an indicium comprising:selecting a print resolution; and printing an indicium on a substrate,at least a portion of the indicium being printed with the selected printresolution, the indicium including at least one symbol, the at least onesymbol including resolution data that is indicative of the selectedprint resolution.
 9. The method according to claim 8, wherein selectinga print resolution includes selecting a horizontal resolution factor anda vertical resolution factor.
 10. The method according to claim 8,wherein printing an indicium includes printing the resolution data inencrypted form.
 11. The method according to claim 8, wherein the atleast one symbol is part of a barcode.
 12. The method according to claim8, further comprising: performing a random process; wherein selecting aprint resolution is performed based at least in part on a result of therandom process.
 13. The method according to claim 8, wherein thesubstrate is an envelope.
 14. A method for verifying an indiciumcomprising: examining the indicium to determine a first print resolutioncharacteristic of at least a portion of the indicium; extracting atleast one symbol included in the indicium, the at least one symbolspecifying a second print resolution that indicates a resolution thatshould have been used to print the at least a portion of the indicium;and comparing the first print resolution characteristic with the secondprint resolution characteristic to determine whether the first printresolution characteristic matches the second print resolutioncharacteristic.
 15. The method according to claim 14, wherein extractingat least one symbol includes reading a barcode that is part of theindicia.
 16. The method according to claim 15, wherein the barcode is atwo-dimensional barcode.
 17. The method according to claim 13, whereinthe indicium is a postage indicium.
 18. The method according to claim14, further comprising: decrypting the at least one symbol.
 19. A methodof printing a postage indicium using a postage meter, the methodcomprising: selecting a print resolution based on predetermined data;and printing at least a portion of the postage indicium with theselected print resolution.
 20. The method according to claim 19, whereinthe predetermined data includes at least one of a calendar date, acurrent day of the week, a state or province in which the postage meteris located, a postal zone in which the postage meter is located, acurrent value of a register of the postage meter, and a random process.21. The method according to claim 19, wherein the postage indiciumincludes resolution data that is indicative of the selected printresolution.
 22. The method according to claim 21, wherein the resolutiondata is represented by a barcode that is part of the postage indicia.23. A postage meter comprising: means for selecting a print resolutionbased on at least one of: (a) a calendar date, (b) a current day of theweek, (c) a state or province in which the postage meter is located, (d)a postal zone in which the postage meter is located, (e) a current valueof a register of the postage meter, and (f) a random process; and printmeans, responsive to the means for selecting, for printing at least aportion of a postage indicium with the selected print resolution. 24.The postage meter according to claim 23, wherein the postage indiciumincludes resolution data that is indicative of the selected printresolution.
 25. The postage meter according to claim 24, wherein theresolution data is represented by a barcode that is part of the postageindicium.